Gitlab?

Firstly, fantastic service!! It just works (as long as you have a proper version tag..!)

## Description
Specify `gitlab.com` instead of `github.com` in the URL to use repo's hosted at gitlab.com.

## Steps to Reproduce
`wget -qO- gobinaries.com/gitlab.com/pepa65/enc |PREFIX=. sh` gives:
`Error: Failed to resolve requested version`
